Gas turbine engine design strives for efficiency, performance and reliability. Efficiency and performance enhancement result from elevated combustion temperatures that increase thermodynamic efficiency, specific thrust and maximizes power output. Higher gas flow temperatures also increase thermal and mechanical loads, particularly on the turbine airfoils exposed to combustion gases. Higher thermal and mechanical loads result from higher gas flow temperatures and tend to reduce service life, reduce reliability of airfoils, and increase the operational costs associated with maintenance and repairs.
Therefore, there continues to be a need for efficient cooling schemes, for turbine airfoils to deal with high gas temperatures, that can be fine tuned and adapted to specific problem areas preferably with minimal changes to established design, manufacturing processes, replacement parts and maintenance protocols.